A Coordination Strategy for TixSn1–xO2 Solid Solution Nanocubes Wrapped by Reduced Graphene Oxide as a Candidate for Lithium‐Ion‐Battery Anodes

Abstract

AbstractA series of TixSn1–xO2 (0≤x≤1) solid solution nanocubes wrapped by reduced graphene oxide (TixSn1–xO2/rGO, TSGC) were designed and synthesized for the application exploration as anode material in lithium ion batteries. When graphene oxide (GO) and K2TiO(C2O4)2 (PTO) were mixed in aqueous ambience, the TiO(C2O4)22− ions were not absorbed onto GO surface by the strong electrostatic repulsion force of the similarly negative‐charged surfaces. When Sn4+ ions were added to the mixture, they were easily adsorbed onto the GO surface. At the same time, Sn4+ ions were also easily coordinated by the carboxyl groups of the PTO species. After the followed hydrothermal and heat treatments, the desired 3D nanoarchitecture composites were obtained. Interestingly, in this TixSn1–xO2/rGO series, the Ti0.74Sn0.26O2/rGO sample exhibited the highest specific capacity of 514 mA h g−1 at 0.1 A g−1 even after 1000th cycles (nearly 100 % efficiency). Such promising electrochemical results are attributed to the 3D integrated structure by achieving better electrical contact between the active materials to shorten ion transport pathways, which highlights the synergistic effect from combining the TixSn1–xO2 nanocubes and rGO films. Additionally, the lithium storage mechanism of the as‐prepared TixSn1–xO2/rGO has been studied via in‐situ X‐ray diffraction (XRD) measurements for the first time.